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Full-Text Articles in Engineering

Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald Jan 2017

Cyberpdx: A Camp For Broadening Participation In Cybersecurity, Wu-Chang Feng, Robert Liebman, Lois Delcambre, Michael Mooradian Lupro, Tim Sheard, Scott Britell, Gerald W. Recktenwald

University Studies Faculty Publications and Presentations

With society’s increasing dependence on technology infrastructure, the importance of securing the computers, networks, data, and algorithms that run our digital and physical lives is becoming critical. To equip the next generation of citizens for the challenges ahead, an effort is underway to introduce security content early in a student’s academic career. It is important that these efforts broaden participation and increase diversity in the field. While many camps and curricula focus on introducing technical content and skills related to cybersecurity, such approaches can prematurely limit how students view career opportunities in the field, potentially limiting those who ultimately pursue …


Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper Jan 2017

Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper

Civil and Environmental Engineering Master's Project Reports

Vehicle speed has long been one, if not the primary contributing factor to crashes, influencing both the probability and severity. Within the Portland metro area arterials have the highest serious crash rate per road mile and vehicle miles travelled. (Metro, 2012) The purpose of this research is to compile vehicle speeds along select arterial roadways within the Portland metro area and comparing it to applicable crash data. The roadway segment of SE Foster Road between SE 52nd avenues and SE 82nd avenues was selected, due to the simplicity of the physical as-built roadway properties along with available Bluetooth …


City Of Gresham Stormwater Retrofit Master Plan, Teresa F. Huntsinger Jan 2017

City Of Gresham Stormwater Retrofit Master Plan, Teresa F. Huntsinger

Civil and Environmental Engineering Master's Project Reports

The Stormwater Retrofit Master Plan identifies more than 50 stormwater retrofit project opportunities across three watersheds in the City of Gresham. The retrofit projects are prioritized in a scoring system to evaluate the costs and benefits of diverse project sizes and types. Project types range from bioswales and planters in city parking lots and along arterial roads, to regional end-of-pipe facilities and retrofits of existing detention ponds. Top projects will move forward for further assessment, design and construction, helping the city achieve its water quality improvement goals. The scoring system may be used to evaluate additional projects in the future.


Fifty-Plus-Year Postflight Analysis Of First Fluid Experiment Aboard A Spacecraft, Mark M. Weislogel, Yongkang Chen, William J. Masica, Fred J. Kohl, Robert D. Green Jan 2017

Fifty-Plus-Year Postflight Analysis Of First Fluid Experiment Aboard A Spacecraft, Mark M. Weislogel, Yongkang Chen, William J. Masica, Fred J. Kohl, Robert D. Green

Mechanical and Materials Engineering Faculty Publications and Presentations

This year marks the 55th anniversary of the first fluid physics experiment performed aboard a spacecraft during the Mercury-Atlas 7 mission. Since then, NASA has conducted over 80 fluids physics experiments aboard a variety of spacecraft, many of which have enhanced the understanding of large-length-scale capillary phenomena relevant to liquid management in the weightless state. As both celebration and demonstration, the Mercury-Atlas 7 fluids experiment is revisited in light of the current understanding of large-length-scale capillary fluidics. Employing a modern numerical tool, a rich variety of experimental outcomes are discovered that were not observed during the flight experiment. Interestingly, experimental …


Reversible Control Of The Magnetization Of Spinel Ferrites Based Electrodes By Lithium-Ion Migration, Guodong Wei, Lin Wei, Dong Wang, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao Jan 2017

Reversible Control Of The Magnetization Of Spinel Ferrites Based Electrodes By Lithium-Ion Migration, Guodong Wei, Lin Wei, Dong Wang, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

Lithium-ion (Li-ion) batteries based on spinel transition-metal oxide electrodes have exhibited excellent electrochemical performance. The reversible intercalation/deintercalation of Li-ions in spinel materials enables not only energy storage but also nondestructive control of the electrodes’ physical properties. This feature will beneft the fabrication of novel Li-ion controlled electronic devices. In this work, reversible control of ferromagnetism was realized by the guided motion of Li-ions in MnFe2O4 and γ-Fe2O3 utilizing miniature lithium-battery devices. The in-situ characterization of magnetization during the Li-ion intercalation/deintercalation process was conducted, and a reversible variation of saturation magnetization over 10% was observed …


Anisotropic Character Of Low-Order Turbulent Flow Descriptions Through The Proper Orthogonal Decomposition, Nicholas Hamilton, Murat Tutkun, Raúl Bayoán Cal Jan 2017

Anisotropic Character Of Low-Order Turbulent Flow Descriptions Through The Proper Orthogonal Decomposition, Nicholas Hamilton, Murat Tutkun, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Proper orthogonal decomposition (POD) is applied to distinct data sets in order to characterize the propagation of error arising from basis truncation in the description of turbulence. Experimental data from stereo particle image velocimetry measurements in a wind turbine array and direct numerical simulation data from a fully developed channel flow are used to illustrate dependence of the anisotropy tensor invariants as a function of POD modes used in low-order descriptions. In all cases, ensembles of snapshots illuminate a variety of anisotropic states of turbulence. In the near wake of a model wind turbine, the turbulence field reflects the periodic …


Relative Sea-Level Trends In New York City During The Past 1500 Years, Andrew C. Kemp, Troy D. Hill, Christopher H. Vane, Niamh Cahill, Philip M. Orton, Stefan A. Talke, Andrew C. Parnell, Kelsey Sanborn, Ellen K. Hartig Jan 2017

Relative Sea-Level Trends In New York City During The Past 1500 Years, Andrew C. Kemp, Troy D. Hill, Christopher H. Vane, Niamh Cahill, Philip M. Orton, Stefan A. Talke, Andrew C. Parnell, Kelsey Sanborn, Ellen K. Hartig

Civil and Environmental Engineering Faculty Publications and Presentations

New York City (NYC) is threatened by 21st-century relative sea-level (RSL) rise because it will experience a trend that exceeds the global mean and has high concentrations of low-lying infrastructure and socioeconomic activity. To provide a long-term context for anticipated trends, we reconstructed RSL change during the past ~1500 years using a core of salt-marsh sediment from Pelham Bay in The Bronx. Foraminifera and bulk-sediment δ13C values were used as sea-level indicators. The history of sediment accumulation was established by radiocarbon dating and recognition of pollution and land-use trends of known age in down-core elemental, isotopic, and pollen …


Issues In Trip Generation Methods For Transportation Impact Estimation Of Land Use Development: A Review And Discussion Of The State-Of-The-Art Approaches, Kristina Marie Currans Jan 2017

Issues In Trip Generation Methods For Transportation Impact Estimation Of Land Use Development: A Review And Discussion Of The State-Of-The-Art Approaches, Kristina Marie Currans

Civil and Environmental Engineering Faculty Publications and Presentations

As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate and robust means for estimating transportation impacts for site-level development review. This paper is a review of the state-of-the-art trip generation methods for land use transportation impact estimation. First, it provides an overview of the more recent available and peer-reviewed estimation methods. Second, the authors offer a discussion of the successes of state-of-the-art approaches using common themes of research to identify corresponding consistency with theories of travel behavior and urban economics. These themes …


Accessibility, Income, And Person Trip Generation: Multilevel Model Of Activity At Food Retail Establishments In Portland, Oregon, Kristina Marie Currans, Kelly Clifton Jan 2017

Accessibility, Income, And Person Trip Generation: Multilevel Model Of Activity At Food Retail Establishments In Portland, Oregon, Kristina Marie Currans, Kelly Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall person-trip rates at similarly-sized establishments of the same land use do not vary across a region. This is an assumption of convenience to permit the adjustment of ITE Trip Generation vehicle trip rates for use in different urban environments. However, this assumption is inconsistent with theories of urban economics, which recognize that businesses pay a premium to locate in areas with high levels of accessibility to attract more customers. In …


Coupling Of Sea Level And Tidal Range Changes, With Implications For Future Water Levels, Adam T. Devlin, David A. Jay, Stefan Talke, Edward D. Zaron, Jiayi Pan, Hui Lin Jan 2017

Coupling Of Sea Level And Tidal Range Changes, With Implications For Future Water Levels, Adam T. Devlin, David A. Jay, Stefan Talke, Edward D. Zaron, Jiayi Pan, Hui Lin

Civil and Environmental Engineering Faculty Publications and Presentations

Are perturbations to ocean tides correlated with changing sea-level and climate, and how will this affect high water levels? Here, we survey 152 tide gauges in the Pacific Ocean and South China Sea and statistically evaluate how the sum of the four largest tidal constituents, a proxy for the highest astronomical tide (HAT), changes over seasonal and interannual time scales. We find that the variability in HAT is significantly correlated with sea-level variability; approximately 35% of stations exhibit a greater than ±50 mm tidal change per meter sea-level fluctuation. Focusing on a subset of three stations with long records, probability …


Minimization Of Quantum Circuits Using Quantum Operator Forms, Martin Lukac, Michitaka Kameyama, Marek Perkowski, Pawel Kerntopf Jan 2017

Minimization Of Quantum Circuits Using Quantum Operator Forms, Martin Lukac, Michitaka Kameyama, Marek Perkowski, Pawel Kerntopf

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper we present a method for minimizing reversible quantum circuits using the Quantum Operator Form (QOF); a new representation of quantum circuit and of quantum-realized reversible circuits based on the CNOT, CV and CV† quantum gates. The proposed form is a quantum extension to the well known Reed-Muller but unlike the Reed-Muller form, the QOF allows the usage of different quantum gates. Therefore QOF permits minimization of quantum circuits by using properties of different gates than only the multi-control Toffoli gates. We introduce a set of minimization rules and a pseudo-algorithm that can be used to design circuits …


Marine Mammal Tracks From Two-Hydrophone Acoustic Recordings Made With A Glider, Elizabeth T. Küsel, Tessa Munoz, Martin Siderius, David K. Mellinger, Sara L. Heimlich Jan 2017

Marine Mammal Tracks From Two-Hydrophone Acoustic Recordings Made With A Glider, Elizabeth T. Küsel, Tessa Munoz, Martin Siderius, David K. Mellinger, Sara L. Heimlich

Electrical and Computer Engineering Faculty Publications and Presentations

A multinational oceanographic and acoustic sea experiment was carried out in the summer of 2014 off the western coast of the island of Sardinia, Mediterranean Sea. During this experiment, an underwater glider fitted with two hydrophones was evaluated as a potential tool for marine mammal population density estimation studies. An acoustic recording system was also tested, comprising an inexpensive, off-the-shelf digital recorder installed inside the glider. Detection and classification of sounds produced by whales and dolphins, and sometimes tracking and localization, are inherent components of population density estimation from passive acoustics recordings. In this work we discuss the equipment used …


A Practitioner's Guide To Urban Trip Generation, Kristina Marie Currans Jan 2017

A Practitioner's Guide To Urban Trip Generation, Kristina Marie Currans

TREC Project Briefs

In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously used across the US and Canada. Only recently, with the third edition of the ITE Trip Generation Handbook, have new data and approaches been adopted. In this study NITC researcher Kristina Currans takes aim at understanding issues inherent in the collection and application of ITE’s data and methods in various urban contexts. This technology transfer guide touches on the main findings from this work.


A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov Dec 2016

A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov

Civil and Environmental Engineering Faculty Publications and Presentations

Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment …


Webinar: State-Wide Pedestrian And Bicycle Miles Traveled: Can We Estimate It?, Krista Nordback Dec 2016

Webinar: State-Wide Pedestrian And Bicycle Miles Traveled: Can We Estimate It?, Krista Nordback

TREC Webinar Series

Heard of Vehicle Miles Traveled (VMT)? Wouldn’t it be great to know the corresponding value for walking and cycling?

This webinar discusses options for estimating the miles people walk and bicycle on the state-wide level, by investigating the practical considerations of trying to compute these values for one study state.

What strategies can be used, and what data sources do these require?

How do these strategies compare?

How do PMT/BMT estimates vary based on data?

Find out what researchers found and what obstacles they encountered when they tried to estimate bicycle and pedestrian miles traveled in the State of Washington.


A Multi-Agent System For Adaptive Control Of A Flapping-Wing Micro Air Vehicle, Michal Podhradský Dec 2016

A Multi-Agent System For Adaptive Control Of A Flapping-Wing Micro Air Vehicle, Michal Podhradský

Dissertations and Theses

Biomimetic flapping-wing vehicles have attracted recent interest because of their numerous potential military and civilian applications. In this dissertation is described the design of a multi-agent adaptive controller for such a vehicle. This controller is responsible for estimating the vehicle pose (position and orientation) and then generating four parameters needed for split-cycle control of wing movements to correct pose errors. These parameters are produced via a subsumption architecture rule base. The control strategy is fault tolerant. Using an online learning process, an agent continuously monitors the vehicle's behavior and initiates diagnostics if the behavior has degraded. This agent can then …


Algorithm For Premature Ventricular Contraction Detection From A Subcutaneous Electrocardiogram Signal, Iris Lynn Shelly Dec 2016

Algorithm For Premature Ventricular Contraction Detection From A Subcutaneous Electrocardiogram Signal, Iris Lynn Shelly

Dissertations and Theses

Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates from an ectopic focus within the ventricles rather than from the sinus node in the right atrium. This and other arrhythmias are often diagnosed with the help of an electrocardiogram, or ECG, which records the electrical activity of the heart using electrodes placed on the skin. In an ECG signal, a PVC is characterized by both timing and morphological differences from a normal sinus beat.

An implantable cardiac …


Development Of 3d Accelerometer Testing System, Mohammed Abbas Soudai Alsaedi Dec 2016

Development Of 3d Accelerometer Testing System, Mohammed Abbas Soudai Alsaedi

Dissertations and Theses

Accelerometers are used in numerous industries including aircrafts and missile navigations systems, rotary machines, and electronic devices such as tablets, cell phones, and cameras. Accelerometers of different purposes and specifications are being produced in large quantities. The large demand for accelerometers forces the need for accelerometer testing methodology that is more convenient and accurate. Inertial Micro-Electromechanical Systems Accelerometer (MEMS) require a series of tests that include physical stimuli. One of the key challenges is the cost associated with testing. Therefore, the accurate prediction of the sensor functions not only reduces the testing time but also more importantly contributes to reducing …


Pricing And Reliability Enhancements In The San Diego Activity-Based Travel Model, Joel Freedman Dec 2016

Pricing And Reliability Enhancements In The San Diego Activity-Based Travel Model, Joel Freedman

PSU Transportation Seminars

The estimation of demand for priced highway lanes is becoming increasingly important to agencies seeking to improve mobility and find alternative revenue sources for the provision of transportation infrastructure.

However, many modeling tools fall short of what is required for robust estimates of demand with respect to toll and managed lanes in two key areas:

  • The value-of-time is often aggregate and not consistently defined throughout the model system, and
  • The reliability of transport infrastructure is rarely taken into account.

This presentation describes an effort which implemented recommendations of the Strategic Highway Research Program C04 and L03\L04 tracks on pricing and …


Investigating Co2 Removal By Ca- And Mg-Based Sorbents With Application To Indoor Air Treatment, Elliott T. Gall, Cem Sonat, William W. Nazaroff, Cise Unluer Dec 2016

Investigating Co2 Removal By Ca- And Mg-Based Sorbents With Application To Indoor Air Treatment, Elliott T. Gall, Cem Sonat, William W. Nazaroff, Cise Unluer

Mechanical and Materials Engineering Faculty Publications and Presentations

Indoor carbon dioxide (CO 2 ) levels serve as an indicator of ventilation sufficiency in relation to metabolic effluents. Recent evidence suggests that elevated CO 2 exposure (with or without other bioeffluents) may cause adverse cognitive effects. In shelter-in-place (SIP) facilities, indoor CO 2 levels may become particularly elevated. This study evaluates four low-cost alkaline earth metal oxides and hydroxides as CO 2 sorbents for potential use in indoor air cleaning applications. Sorbents studied were MgO, Mg(OH) 2 , Ca(OH) 2 and commercially available soda lime. Uncarbonated sorbents characterized with nitrogen adsorption porosimetry showed BET surface areas in the 5.6–27 …


Safety Effectiveness Of Pedestrian Crossing Enhancements, Christopher M. Monsere, Miguel Figliozzi, Sirisha Kothuri, Ali Razmpa, Daniel R. Hazel Dec 2016

Safety Effectiveness Of Pedestrian Crossing Enhancements, Christopher M. Monsere, Miguel Figliozzi, Sirisha Kothuri, Ali Razmpa, Daniel R. Hazel

Civil and Environmental Engineering Faculty Publications and Presentations

Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were collected on 191 crossings. Supplemental data items included crossing location information, route characteristics, surrounding land use and crossing enhancement descriptions. Pedestrian volume at the crossing locations was a highly desirable but unavailable data element. To characterize pedestrian activity, a method was developed to estimate ranges for pedestrian crosswalk activity levels based on the land use classification at the census block level and the presence …


Task And Participant Scheduling Of Trading Platforms In Vehicular Participatory Sensing Networks, Heyuan Shi, Xiaoyu Song, Ming Gu, Jiaguang Sun Dec 2016

Task And Participant Scheduling Of Trading Platforms In Vehicular Participatory Sensing Networks, Heyuan Shi, Xiaoyu Song, Ming Gu, Jiaguang Sun

Electrical and Computer Engineering Faculty Publications and Presentations

The vehicular participatory sensing network (VPSN) is now becoming more and more prevalent, and additionally has shown its great potential in various applications. A general VPSN consists of many tasks from task, publishers, trading platforms and a crowd of participants. Some literature treats publishers and the trading platform as a whole, which is impractical since they are two independent economic entities with respective purposes. For a trading platform in markets, its purpose is to maximize the profit by selecting tasks and recruiting participants who satisfy the requirements of accepted tasks, rather than to improve the quality of each task. This …


Using Blind Source Separation And A Compact Microphone Array To Improve The Error Rate Of Speech Recognition, Jeffrey Dean Hoffman Dec 2016

Using Blind Source Separation And A Compact Microphone Array To Improve The Error Rate Of Speech Recognition, Jeffrey Dean Hoffman

Dissertations and Theses

Automatic speech recognition has become a standard feature on many consumer electronics and automotive products, and the accuracy of the decoded speech has improved dramatically over time. Often, designers of these products achieve accuracy by employing microphone arrays and beamforming algorithms to reduce interference. However, beamforming microphone arrays are too large for small form factor products such as smart watches. Yet these small form factor products, which have precious little space for tactile user input (i.e. knobs, buttons and touch screens), would benefit immensely from a user interface based on reliably accurate automatic speech recognition.

This thesis proposes a solution …


Evaluation Of A Supervisor Training Program For Odot’S Ecodrive Program, Donald M. Truxillo, John Macarthur, Leslie B. Hammer, Talya N. Bauer Dec 2016

Evaluation Of A Supervisor Training Program For Odot’S Ecodrive Program, Donald M. Truxillo, John Macarthur, Leslie B. Hammer, Talya N. Bauer

TREC Final Reports

Eco-driving consists of using energy-efficient approaches to driving aimed at reducing fuel consumption and, ultimately, CO2 emissions. A previous study found that an EcoDrive informational campaign was effective at increasing the use of eco-driving behaviors, but only when employees perceived that their supervisor supported the program and when they were personally motivated to perform the eco-driving behaviors. In order to build upon the findings of our previous study, the present study focused on increasing the use of eco-driving behaviors through an informational eco-driving campaign combined with supervisor training to support the use of eco-driving practices.

In this study we collected …


Focused-Based Multifractal Analysis Of The Wake In A Wind Turbine Array Utilizing Proper Orthogonal Decomposition, Naseem Ali, Hawwa Falih Kadum, Raúl Bayoán Cal Nov 2016

Focused-Based Multifractal Analysis Of The Wake In A Wind Turbine Array Utilizing Proper Orthogonal Decomposition, Naseem Ali, Hawwa Falih Kadum, Raúl Bayoán Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Hot-wire anemometry measurements have been performed in a 3×3 wind turbine array to study the multifractality of the turbulent kinetic energy dissipation. A multifractal spectrum and Hurst exponents are determined at nine locations downstream of the hub height, bottom and top tips. Higher multifractality is found at 0.5D and 1D downstream of the bottom tip and hub height. The second order of the Hurst exponent and combination factor shows the ability to predict the flow state in terms of its development. Snapshot proper orthogonal decomposition (POD) is used to identify the coherent and incoherent structures and to reconstruct the stochastic …


Experimental Investigation Of Cfrp Wrapped Square Non-Ductile Reinforced Concrete Columns, Hayder Lateef Al-Khafaji Nov 2016

Experimental Investigation Of Cfrp Wrapped Square Non-Ductile Reinforced Concrete Columns, Hayder Lateef Al-Khafaji

Dissertations and Theses

The use of fiber-reinforced polymers (FRP) for retrofitting or strengthening deficient concrete columns noticeably increased in the past few decades. Plenty of research has been conducted on the behavior of FRP-strengthened circular concrete columns, but far less research has dealt with non-circular columns. In the current study, the focus was to investigate the behavior of square columns with low to medium grade concrete and low steel reinforcement that were strengthened using carbon fiber reinforced polymer (CFRP) wrap. In the experimental portion of this investigation, twelve short square reinforced concrete columns (5" x 5" in cross section and 12" high) were …


An Assessment Of Post-Encroachment Times For Bicycle-Vehicle Interactions Observed In The Field, A Driving Simulator, And In Traffic Simulation Models, Ali Razmpa Nov 2016

An Assessment Of Post-Encroachment Times For Bicycle-Vehicle Interactions Observed In The Field, A Driving Simulator, And In Traffic Simulation Models, Ali Razmpa

Dissertations and Theses

Most safety analysis is conducted using crash data. Surrogate safety measures, such as various time-based measures of time-to-collision can be related to crash potential and used to gain insight into the frequency and severity of crashes at a specific location. One of the most common and acknowledged measures is post-encroachment time (PET) which defines the time between vehicles occupying a conflicting space. While commonly used in studies of motor vehicle interactions, studies of PET for bicycle-vehicle interactions are few. In this research, the PET of bicycle-vehicle interactions measured in the field, a driving simulator, and in a micro-simulation are compared. …


Investigation Of Jet Dynamics In Cross-Flow: Quantifying Volcanic Plume Behavior, Graham Freedland Nov 2016

Investigation Of Jet Dynamics In Cross-Flow: Quantifying Volcanic Plume Behavior, Graham Freedland

Dissertations and Theses

Volcanic eruption columns inject high concentrations of ash into the atmosphere. Some of this ash is carried downwind forming ash clouds in the atmosphere that are hazardous for private and commercial aviation. Current models rely on inputs such as plume height, duration, eruption rate, and meteorological wind fields. Eruption rate is estimated from plume height using relations that depend on the rate of air entrainment into the plume, which is not well quantified. A wind tunnel experiment has been designed to investigate these models by injecting a vertical air jet into a cross-flow. The ratio of the cross-flow and jet …


Designing A Continuously Variable Magnetic Gear, J. Pritchard, Pavithra Padmanathan, Jonathan Z. Bird Nov 2016

Designing A Continuously Variable Magnetic Gear, J. Pritchard, Pavithra Padmanathan, Jonathan Z. Bird

Electrical and Computer Engineering Faculty Publications and Presentations

This paper investigates the performance capabilities of a continuously variable magnetic gearbox that utilizes a flux focusing rotor structure. A fractional slot stator winding is designed to couple to the outer rotor of an existing magnetic gearbox in order to enable the magnetic gearbox to operate with a variable gear ratio.


Technology Trajectory Mapping Using Data Envelopment Analysis: The Ex-Ante Use Of Disruptive Innovation Theory On Flat Panel Technologies, Dong-Joon Lim, Timothy R. Anderson Nov 2016

Technology Trajectory Mapping Using Data Envelopment Analysis: The Ex-Ante Use Of Disruptive Innovation Theory On Flat Panel Technologies, Dong-Joon Lim, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

In this paper, we propose a technology trajectory mapping approach using Data Envelopment Analysis (DEA) that scrutinizes technology progress patterns from multidimensional perspectives. Literature reviews on technology trajectory mappings have revealed that it is imperative to identify key performance measures that can represent different value propositions and then apply them to the investigation of technology systems in order to capture indications of the future disruption. The proposed approach provides a flexibility not only to take multiple characteristics of technology systems into account but also to deal with various tradeoffs among technology attributes by imposing weight restrictions in the DEA model. …